Hate to bump an old thread but I got the ABS and PSM warning today on the way to work......was just driving normally and downshifted to stop and both came on.

I can still drive the car with no issues but after searching through the threads it could be a handle of things

 

Test your MAF.

With a volt meter to pin 5 on the MAF and ground you should get 0.9-1.1VDC with the key in the on position/engine turned off. Then warm up the car and test with the engine running. You should be at 1.4vdc. If you are not you can try cleaning it with electronics cleaner/MAF cleaner then test again. If it is still not good you'll just need a new MAF.

 

I was thinking I may need a new harness....or even the brake switch behind the pedal.

Going to test everything to narrow this down.

Thanks.

 

Get the codes read by Durametric, PST2 or PIWIS.

 

Definitely get the codes read with a good reader. The cheap basic ones may not pick it up; I just went through this myself. I had a MAF error when my mechanic read the codes. I have since replaced it but since I don't drive the car much, I don't know if that solved the problem just yet.

To save you some time, here's all the info I found over the last couple of months. I think it has most everything covered:

•Bad MAF (probably the most common cause).
•Failed Brake Sensor (Solution: replace brake sensor approx $20.00); a quick check is to make sure all the brake lights work.
•Failed or damaged wheel speed sensor (Solution: check datalog codes for left or right sensor failure, swap left and right sensors and see if the failure moves to the opposite side. Replace if code states failure moved to opposite side. Leave sensors alone if code doesn't change.). You can also try cleaning the wheel speed sensors.
•ABS Ring on Axle (Solution: clean the ring)
•Bad Wiring Harness (Testing: Run double 16ga wire from wheel speed sensor directly to ABS box and check for code to clear itself. Solution: Order repair kit and fix harness.) P/N 996-612-958-00
•Bad ABS Module (This is expensive and should be your last resort. Solution: Repair ABS Module)

 

Thanks so much, in my little time today I think I got 90% of the same info you posted

Well as I started the car up to take it to the dealership both the errors went away we tried to read if any codes were logged but it came back empty.

I guess I will clean as many parts as possible as a preventative action and see if it comes back again.

So frustrating at times.

 

I only got the issue occasionally; it usually went away when I re-started the car. Any rough idle at all when it happens?

 

No rough idle, actually drives just like normal.

 

I second the faulty brake pedal switch.
I just had the exact same thing happen to me, the PSM and ABS lights came on when i was coming to a stop. They went away after i restarted the car and came back on intermittently.
After reading through the forums i decided to just chance it and stick a new switch in, worked like a charm.
FWIW, despite the worn out switch, my brake lights were still working, so it's possible for just one of the parts to fail inside the switch. I took the old one apart and sure enough, one of the contacts was worn away.

 

I may get a new switch as well and keep it in the garage in case it comes up again. Can't go wrong for $20.

My issue *should* be the MAF though.

 

I agree it's a cheap fix for peace of mind.

 

Confirmed today that my right front speed sensor is bad. Dealer quoted me $167 for a new part and $120 for install.

Anyone know if there is a better price for purchasing a new sensor.

Thanks in advance.

 

The best price I saw for the sensor (996 606 406 00) was $132.50 and $120.00 (one hour) for the installation seems to be an honest quote.

 

For the MAF, what is the exact part number?

Thanks! and is the MAF the sensor on the left of the engine compartment?

 

Bosch # 0280 218 009

Porsche # 996 606 124 00